This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A346463 #7 Jul 20 2021 04:59:37 %S A346463 0,1,7,93,2159,15841,6141,44731051,8421119,86113647,3331843885, %T A346463 127479517837,103104368637,750599904340651,82824819807611, %U A346463 80500035008073,36170086393773823,49191317521302203051,2460603943675971,12592977287514948283051,89351501819019263845 %N A346463 a(n) = 6 * GaussBinomial(2*n, 2, 2) / denominator(Bernoulli(2*n, 1)). %F A346463 a(n) = (4^n - 2)*(4^n - 1)/Clausen(2*n, 1), where Clausen(n, k) = A160014(n, k). %p A346463 a := n -> (4^n - 2)*(4^n - 1) / mul(i, i=select(isprime, map(i->i+1, numtheory[divisors] (2*n)))): seq(a(n), n = 0..20); %t A346463 Table[6 QBinomial[2 n, 2, 2] / Denominator[BernoulliB[2 n, 1]], {n, 0, 20}] %Y A346463 Cf. A006095, A002445, A160014, A346464. %K A346463 nonn %O A346463 0,3 %A A346463 _Peter Luschny_, Jul 19 2021